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In this work, forward current voltage characteristics for multi quantum wells Al0.33Ga0.67As Schottky diode were measured at temperature range from 100 to 300K. The main parameters of this Schottky diode, such as the ideality factor, barrier height, series resistance and saturation current, have been extracted using both analytical and heuristics methods. Differential Evolution (DE), Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC) have been chosen as candidate heuristics algorithms. While, Cheung technic was selected as analytical extraction method. The obtained results show clearly the high performance of DE algorithms in terms of parameters accuracy, convergence speed and robustness.

We report the capacitance-voltage (C-V) characteristics of multi quantum wells Schottky diode. This diode is based on Aluminum gallium arsenide, which is highly promising wide band gap semiconductor for applications in high power electronic and optoelectronic devices. The elaboration process and the characterization phase have been carried out at Nottingham University. The C-V characteristics have been measured at different temperature ranging from 20K to 400K. The barrier height and effective density were than extracted from 1/(C/A) 2 plot using heuristic algorithm which called ALO (Ant Lion Optimizer).the accuracy of the extraction method is verified through the gotten results.

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Thermally annealed DC sputtered indium tin oxide (ITO) thin films were investigated for improvement in properties. The structural and optoelectronic characteristics of as-grown and air annealed films were studied and correlated to the film deposition time. Raman spectroscopy analysis showed low crystalline quality films for as-grown films and were significantly improved after annealing. X-ray diffraction analysis confirmed the crystallinity of samples with (222) preferential orientation. The 30-min ITO films showed a peak at (400). The films optical study shows an increased transmittance (in the transparency region) with decreasing deposition time, yielding a high transparency of 90% for the 5-and 15-min ITO films annealed at 400°C. The films thickness and optical constants were determined from optical transmission only without interference fringe using a novel method based on particle swarm optimization (PSO) algorithm. The absorption coefficient and calculated refractive index decreased with increasing deposition time and their value reduced further after annealing treatment. The 30-min ITO films showed a comparable low resistivity of 4 9 10 -3 X cm before and after annealing as determined by Hall effect measurements. This observation confirms their non-sensitivity to the oxygen post-contamination that resulted from (400) orientation. A shift of the absorption edge towards shorter wavelengths accompanied with an increase in the optical bandgap before and after annealing with decreasing thickness were observed. We have demonstrated that the optical parameters such as the optical gap depend mainly on the electrical parameters such as the carrier concentration.